In general, when a heavy object is present in the front of a front axle of a vehicle, the yaw moment of inertia acts in steering. For this reason, a shorter front overhang has been demanded. In particular, such a front overhang has been strongly demanded for, e.g., a sports car requiring a high vehicle motion performance.
In order to shorten a front overhang, the front-to-rear length of a head lamp unit may be shortened.
However, in a recent head lamp unit, associated structures such as an active front lighting system (AFS) drive device and an LED heat sink for cooling LEDs used as a light source are provided, and tendency shows that the size of the head lamp unit increases.
Note that the AFS drive device is a drive device configured to change a irradiation direction of a head lamp according to a vehicle traveling state.
In the case of providing an additional lamp such as an accessory, the size of the head lamp unit further increases. Thus, it is difficult to shorten the front-to-rear length of the head lamp unit.
When the front overhang is shortened for ensuring the vehicle motion performance (reducing the yaw moment of inertia) and ensuring design properties (fine appearance), there are concerns about contact with the periphery of the head lamp unit and lowering of cooling performance
Patent Literature 1 discloses a head lamp unit configured such that an accessory lamp and an AFS drive device are embedded in an LED head lamp. However, in a typical structure disclosed in Patent Literature 1, an LED heat sink including heat dissipation fins and the AFS drive device are arranged in a vehicle width direction or a vehicle lower direction. For this reason, the front-to-rear length of a vehicle front lamp (a head lamp unit) cannot be sufficiently shortened, and further improvement needs to be made for dealing with overhang shortening.